The provision of the locking member and handle for screen closures particularly those associated with sliding glass doors and windows has presented a challenge to the designers of these types of closures. The screen, unnecessary adjunct to a door or window is often overlooked insofar as the hardware used to open and close the screen. There is typically very little clearance between the screen and the adjacent door so that the handle must be of minimum thickness. It cannot interfere with the movement of the door or window and it cannot effectively be produced and then secured to the screen frame by punching or notching the frame as is commonly done in the lock mechanisms of sliding doors. This later is true because the frame for a sliding screen is usually relatively small and any punching or weakening of any type, particularly at the middle region between top and bottom can result in the door frame collapsing when someone applies abnormal force to the screen frame.
Of additional significance is the fact that the screen door or window constitutes a relatively low priced item and the handle and latch mechanism, although it must meet all of the foregoing requirements, must also be of minimum cost and high degree of reliability.
I have faced a similar problem in the field of frameless sliding window latches and have produced the one piece latch and handle mechanism disclosed and claimed in my U.S. Pat. No. 4,114,934. In that Patent, an integral pair of jaws served to engage and lock a window in the closed position and include an upstanding or outward extending handle portion to be manipulated by the user. Such arrangement however is neither required nor allowed for sliding screen closures because of the thickness clearance limitations and the normal lack of any member for the jaws to close upon.